Equine recurrent uveitis in western Canadian prairie provinces: A retrospective study (2002-2015)

Abstract

The objectives of this study were to determine the demographics of horses with equine recurrent uveitis (ERU) presenting to the Western College of Veterinary Medicine and to describe and compare the prognosis of ERU in the Appaloosa with that in other breeds. Horses diagnosed with ERU by a veterinary ophthalmologist between 2002 and 2015 were included. Eye lesions were classified as mild, moderate, or severe based on clinical manifestations. Breed, age, severity, blindness, and final outcome were evaluated. Thirty-two horses fit the inclusion criteria; 62.5% were Appaloosas. Mean age at presentation was 12.13 ± 4.6 years. Equine recurrent uveitis was bilateral in 93.6% of horses and was severe in 59.4% of eyes at presentation. Bilateral blindness was present in 59.4% of horses at last follow-up. Of 27 horses available for follow-up, 63% were euthanized due to ERU. No significant differences in age, severity, blindness, or rate of euthanasia were noted between Appaloosas and other breeds. The Appaloosa is at increased risk for ERU, which is a devastating ocular disease.

Figure 1

Clinical manifestations of severe equine recurrent uveitis. Photographs of a — Phthisis bulbi in the right eye of a 16-year-old Appaloosa; b — Miosis, cataract, and posterior synechia in an 8-year-old Thoroughbred; c — Secondary glaucoma in a 19-year-old Quarter Horse; d — Miosis, cataract and posterior synechia in an 8-year-old Thoroughbred.